Nontemperature sensitive memory foam of mdi system suitable for horizontal foaming process

ABSTRACT

A MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process, is made by mainly using polyether polyol and polymer polyol as main material, then adding three additives isocyanate and foaming agent, the pore adjusting agent and catalyst. The polyether polyol is polyoxypropylene glycerol with molecular weight of 700, the polymer polyol is high activity grafting polyether, the isocyanate is modified polyphenyl methane diisocyanate, wherein a polyoxypropylene trihydroxy ether with the molecular weight of 4800 is added to the polyether polyol, polyol chain extender is added to said additives.

A MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process

TECHNICAL FIELD

The present invention relates to a MDI system non-temperature sensitive memory sponge with density in 40-70 D, in particular to a MDI system non-temperature sensitive memory sponge prepared by mainly using of polyether polyol with molecular weight of 700 and isocyanate as main materials, then adding the additives.

BACKGROUND TECHNOLOGY

With the improvement of living standards, comfort requirements of people on the home furnishing are also getting higher and higher. Ordinary soft sponge products have always been widely adopted by furniture manufacturers because of their soft and elastic. However, in the use process, ordinary soft sponge products are disadvantages of high rebound pressure for human vascular, hot in the summer and hard in texture in the winter and poor comfortability, so that application category of the ordinary soft sponge is limited.

In order to make up for the inadequacy of ordinary soft sponge, a molding MDI system non-temperature sensitive memory sponge currently is introduced on the market, which sponge is characterized that automatically adjusting the shape according to body shape and temperature, effectively defusing the humans pressure to zero, offsetting the reverse motivation, providing the most average and true support, making the part contacted in length time of the body to be at the state of no pressure, not hindering the blood circulation and not easily producing fatigue and soreness. When non-temperature sensitive memory sponge is used in hospitals, it also can provide maximum comfort for the patient, and can effectively prevent the bedsores. The ordinary soft sponge can hardly compete with non-temperature sensitive memory sponge on the superiority. But, the sponge manufacturing has been adopting the injection molding process. Using mould as the carrier, a sponge with a volume not greater than 0.5 m³ can only be made at a time, which can only apply to produce small products such as pillow, toys. The production process seriously hinders the further expansion of non-temperature sensitive memory sponge application domain, does not adapt to product large sponge such as mattresses, and manufacture by one mould is not only unfit for large-scale production but also low efficiency.

CONTENTS OF INVENTION

The main task of the present invention is to provide a MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process, in particular to a MDI system non-temperature sensitive memory sponge with high tear strength and better tensile rate made by adjusting ingredient of sponge system, which is suitable for flat foam foaming process.

In order to solve the above technical problems, a MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process of the present invention, is made by mainly using polyether polyol and polymer polyol as main material, then adding three additives isocyanate and foaming agent, the pore adjusting agent and catalyst. Said polyether polyol is polyoxypropylene glycerol with molecular weight of 700, said polymer polyol is high activity grafting polyether, said isocyanate is modified polyphenyl methane diisocyanate, characterized in that: a polyoxypropylene trihydroxy ether with the molecular weight of 4800 is added to said polyether polyol, polyol chain extender is added to said additives; in the above-mentioned composition, the total mass portions of polyether polyol and polymer polyol are 100 parts, the foaming agent is 1.5-3 mass parts, the mass portions of isocyanate are determined according to the above-mentioned all components containing hydroxyl value multiplied by the hydroxyl value corresponding to each component and then multiplied by the constant 0.155, plus the foaming agent not containing hydroxyl value, which foaming agent is calculated by the foaming agent multiplied by a constant 9.665; at last the above-mentioned total number is multiplied by hardness index and then finally obtained the mass portions of isocyanate.

Further, the addition amount of said polyoxypropylene trihydroxy ether with molecular weight of 4800 is 60-80% of the weight portions of main material polyol; the weight portions of the polyol chain extender are 2-5 parts of the weight portions of main material polyol.

Further, said polyol chain extender is polyether polyol with molecular weight of 100, such as polyoxyethylene glycol.

The production principle of the present invention is: it is green that using environmentally friendly MDI to instead of traditional dangerous chemical product TDI to produce gas sense sponge, but the gas sense sponge foamed from MDI is general with relatively poor tear strength, so it can only be made to small sponge block by mould and not satisfy to large area whole sponge such as a mattress. In the experiment, the obtained tear strength is associated with polyether polyol with molecular weight of 4800, the reason of cannot realizing the foam production with the large area is that the original mold production ingredient is located in a flat foam process, the internal structure of obtained sponge is hollow, similar to the column structure with poor link and easy to tear. In view of this phenomenon, the present invention improves the production ingredient of the traditional mould, adding a certain amount of chain extender, and adjust the ratio of other relevant component, so that the sponge internal structure is change from cylindrical structure to mesh structure during the large area flat foam foaming, which increase the link points of sponge internal structure and then meet process requirements of large area whole production suitable for flat foam foaming.

In the present invention, because of the improvement of the ingredient and the sponge internal structure is mesh, when in use, the body heat can follow the sponge mesh structure fast dispersion to form “capillary” phenomenon, said phenomenon make the sponge interior not to gather outside heat, increase permeability and with better comfort.

The present invention has the advantages that: MDI system sponge using the above-mentioned ingredient, which using the high molecular weight polyether polyol used as the pore adjusting agent as main material and supplemented by chain extender, can be used to produce big block sponge on the flat foam foaming line, breaking the limit that the original MDI system gas sense sponge can only be used to produce small area sponge by mould.

To achieve line operations by adopting the above-mentioned ingredient, with the advantages of quick discharge and high efficiency, the speed is improved at least 100 times comparing with the general MDI system gas sensing sponge injection molding; importantly, the line does not require one kind of shape sponge with one mould, only need the whole sponge that be produced well to be cut into the required shape by cutting knife, reducing the unnecessary mould cost.

MODE OF CARRYING OUT THE INVENTION

The materials for MDI system non-temperature sensitive memory sponge with a density of 40-70 D of the present invention are the following components and proportion: said production components and weight portions proportion are as follows: in the cases of 100 parts of polyol, isocyanate is 40-70 parts, the pore adjusting agent is 1.4-2.5 parts, catalyst is 0.1-0.4 parts, the main foaming agent water 1.5-2.5 parts, the auxiliary foaming agent methylene chloride 0-10 parts; the polyol chain extender 2-5 parts.

Said polyether glycol is the polyether polyols with following weight portions: polyether polyol with molecular weight of 700: 10-20 parts; polyether polyol with molecular weight of 4800: 60-80 parts, polymer polyol: 5-20 parts.

Above-mentioned polyol chain extender is polyoxyethylene glycol of polyether polyol with molecular weight of 100.

After above-mentioned materials are chosen, each kind of material according to the percentage is separately put in each container, and the temperature of the whole raw materials is maintained at 22-25° C. for subsequent productions.

After the materials are alone configuration, the materials are subsequently mixing. Material mixing steps are: connecting the above independent container through a pipeline to the mixer, providing respectively with a measuring rod and an electromagnetic valve at several pipe mouths; opening the electromagnetic valve when the material flow out, controlling flow rate precisely through the metering rod, flowing material to the mixer, mixing in the mixer till solution to mix evenly. Mixed solution is injected to distributor through communicated jet connected with mixer, the solution is distributed evenly on the track within the line oven with 150-320 kg/min flow velocity by the distributor, the oven temperature is 30-40° C.; mixed solution is continuous foaming with a speed of 0.05-0.09 m/s in the oven, track is continuously moving, foamed part is pushed forward, to make room for the subsequent foaming materials.

In the process, the baffles are provided on both sides of line track, the baffles determine the width of the sponge, the height of the sponge is determined by the sponge density, track transmission velocity and the flow rate of the mixed solution.

EXAMPLE 1

Choosing the following materials as the sponge raw materials: in the case of 100 parts by weight of polyols, modified polyphenyl methane diisocyanate is 61 weight parts, the pore adjusting agent polysiloxane polyether copolymer 2 weight parts, catalyst trivinyl diamine solution is 0.2 weight parts, the main foaming agent water 2.4 weight parts, the auxiliary foaming agent methylene chloride is 5 weight parts, the chain extender polyether polyol with molecular weight of 100: polyoxyethylene glycol is 4 weight parts.

Above-mentioned 100 parts of polyols are consists of the following four components in the following proportions: 70 parts of Mn4800 polyether polyols, 20 parts of Mn700 polyether polyols, 10 parts of polymer polyols.

Above-mentioned polyether polyols are mixture of a variety of high molecular weight polyether polyols. In this example, polyether polyol with molecular weight of 4800 specifically is polyoxypropylene trihydroxy ether; polyether polyol with molecular weight of 700 specifically is polyoxypropylene glycerol alcohol, polymer polyol specifically is high activity grafted polyether.

Above-mentioned raw materials are mix at a temperature of 22-25° C. to form a mixed solution, and the mixed solution is distributed within the oven having a width of 2 meters through the distributor at 215 kg/s flow rate, track moves forward at the transmission velocity of 3.5 meters in the oven with a temperature of 30-40° C., continuous big block sponge with a density of 40 D and height of 78 cm is formed.

The sponge produced by the process, is detected according to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic” (remarks: as there is no detected standard for this product, this product is temporarily detected by this standard), the detection results are:

Sample test testing item unit value recovery time S 10.3 75% compression permanent deformation % 64.9 rebound degree % 10 tensile strength KPa 43.3 percentage of elongation % 258.1 tear strength N/cm 1.01 odor level level 3.0 tensile strength rate of change after dry % 16.2 heat aging tensile strength rate of change after wet % 3.2 heat aging 65% 25% indentation ratio — 2.6 40% indentation hardness value of the % 4.0 loss after constant load repeated indentation fatigue temperature and humidity sensitivity — 2.2

It can be obtained by summarizing above table that, in the above-mentioned conditions, parameters such as tear strength of the example product basically close to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic”, and the produced product is qualified.

Using the line production mode of flat foam foaming process, its support degree tends to be consistent with ordinary sponge support degree, the body of the sponge does not collapse. Advantages are: compared with previous injection molding, the speed increases at least 100 times, the follow-up molding of the product can adopt abnormity cutting molding, its molded shape changes in myriads forms, the product can be any shape that we can imagine. Because of using cutting means in the molding, not only saving raw materials, but reducing the amount of mould costs, the economic benefits are significant.

EXAMPLE 2

Choosing the following materials as the sponge raw materials: in the case of 100 parts of polyols, modified polyphenyl methane diisocyanate is 53 parts, the pore adjusting agent polysiloxane polyether copolymer is 2, catalyst trivinyl diamine solution is 0.18 parts, the main foaming agent water 2.3 parts, the auxiliary foaming agent methylene chloride is 2 parts, the chain extender polyether polyol with molecular weight of 100: polyoxyethylene glycol 3 parts. Above-mentioned 100 parts of polyols are consists of the following four components in the following proportions: 75 parts of Mn4800 polyether polyols, 15 parts of Mn700 polyether polyols, 10 parts of polymer polyols.

Above-mentioned polyether polyols are mixture of a variety of high molecular weight polyether polyols. In this example, polyether polyol with molecular weight of 4800 specifically is polyoxypropylene trihydroxy ether; polyether polyol with molecular weight of 700 specifically is polyoxypropylene glycerol alcohol, polymer polyol specifically is high activity grafted polyether.

Above-mentioned raw materials are mix at a temperature of 22-25° C. to form a mixed solution, and the mixed solution is distributed within the oven having a width of 2 meters through the distributor at 250 kg/min flow rate, track moves forward at the transmission velocity of 3.5 meters in the oven with a temperature of 30-40° C., continuous big block sponge with a density of 46 D and height of 78 cm is formed by the line production mode of flat foam foaming process.

Sample test testing item unit value recovery time S 10.3 75% compression permanent deformation % 48.9 rebound degree % 10 tensile strength KPa 51 percentage of elongation % 258.1 tear strength N/cm 1.4 odor level level 3.0 tensile strength rate of change after dry % 16.2 heat aging tensile strength rate of change after wet % 3.2 heat aging 65% 25% indentation ratio — 2.6 40% indentation hardness value of the % 4.0 loss after constant load repeated indentation fatigue temperature and humidity sensitivity — 2.2

It can be obtained by summarizing above table that, in the above-mentioned conditions, parameters such as tear strength of the example product basically close to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic”, and the produced product is qualified.

EXAMPLE 3

Choosing the following materials as the sponge raw materials: in the case of 100 parts of polyols, modified polyphenyl methane diisocyanate is 50 parts, the pore adjusting agent polysiloxane polyether copolymer is 1.8, catalyst trivinyl diamine solution is 0.18 parts, the main foaming agent water 2.3 parts, the chain extender polyether polyol: polyoxyethylene glycol 2 parts.

Above-mentioned 100 parts of polyols are consists of the following four components in the following proportions: 80 parts of Mn4800 polyether polyols, 10 parts of Mn700 polyether polyols, 10 parts of polymer polyols.

Above-mentioned polyether polyols are mixture of a variety of high molecular weight polyether polyols. In this example, polyether polyol with molecular weight of 4800 specifically is polyoxypropylene trihydroxy ether; polyether polyol with molecular weight of 700 specifically is polyoxypropylene glycerol alcohol, polymer polyol specifically is high activity grafted polyether.

Above-mentioned raw materials are mix at a temperature of 22-25° C. to form a mixed solution, and the mixed solution is distributed within the oven having a width of 2 meters through the distributor at 250 kg/min flow rate, track moves forward at the transmission velocity of 3.3 meters in the oven with a temperature of 30-40° C., continuous big block sponge with a density of 50 D and height of 76 cm is formed by the line production mode of flat foam foaming process.

The sponge produced by the process, is detected according to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic” (remarks: as there is no detected standard for this product, this product is temporarily detected by this standard), the detection results are:

Sample test testing item unit value recovery time S 12 75% compression permanent deformation % 55.3 rebound degree % 10 tensile strength KPa 50 percentage of elongation % 258.1 tear strength N/cm 1.08 odor level level 3.0 tensile strength rate of change after dry % 16.2 heat aging tensile strength rate of change after wet % 3.2 heat aging 65% 25% indentation ratio — 2.6 40% indentation hardness value of the % 4.0 loss after constant load repeated indentation fatigue temperature and humidity sensitivity — 2.1

It can be obtained by summarizing above table that, in the above conditions, parameters such as tear strength of the example product basically close to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic”, and the produced product is qualified.

EXAMPLE 4

Choosing the following materials as the sponge raw materials: in the case of 100 parts of polyols, modified polyphenyl methane diisocyanate is 52 parts, the pore adjusting agent polysiloxane polyether copolymer is 1.6, catalyst trivinyl diamine solution is 0.16 parts, the main foaming agent water 2.1 parts; the chain extender polyether polyol 5 parts. Above-mentioned 100 parts of polyols are consists of the following four components in the following proportions: 60 parts of Mn4800 polyether polyols, 20 parts of Mn700 polyether polyols, 20 parts of polymer polyols.

Above-mentioned polyether polyols are mixture of a variety of high molecular weight polyether polyols. In this example, polyether polyol with molecular weight of 4800 specifically is polyoxypropylene trihydroxy ether; polyether polyol with molecular weight of 700 specifically is polyoxypropylene glycerol alcohol, polymer polyol specifically is high activity grafted polyether.

Above-mentioned raw materials are mix at a temperature of 22-25° C. to form a mixed solution, and the mixed solution is distributed within the oven having a width of 2 meters through the distributor at 285 kg/min flow rate, track moves forward at the transmission velocity of 3.5 meters in the oven with a temperature of 30-40° C., continuous big block sponge with a density of 55 D and height of 74 cm is formed.

The process for the production of sponge, according to GB/T24451-2009 “ slow rebound polyurethane foam ” standards for detection (attached: as the product is not detected by standard, therefore temporarily using the standard detection), the detection results:

Sample test testing item unit value recovery time S 11 75% compression permanent deformation % 60.2 rebound degree % 10 tensile strength KPa 43.3 percentage of elongation % 247.3 tear strength N/cm 1.2 odor level level 3.0 tensile strength rate of change after dry % 16.2 heat aging tensile strength rate of change after wet % 3.2 heat aging 65% 25% indentation ratio — 2.6 40% indentation hardness value of the % 5.0 loss after constant load repeated indentation fatigue temperature and humidity sensitivity — 2.2

It can be obtained by summarizing above table that, in the above conditions, parameters such as tear strength of the example product basically close to the standard GB/T24451-2009 “slow rebound soft polyurethane foam plastic”, and the produced product is qualified. 

1. A MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process, is made by mainly using polyether polyol and polymer polyol as main material, then adding three additives isocyanate and foaming agent, the pore adjusting agent and catalyst, said polyether polyol is polyoxypropylene glycerol with molecular weight of 700, said polymer polyol is high activity grafting polyether, said isocyanate is modified polyphenyl methane diisocyanate, wherein a polyoxypropylene trihydroxy ether with the molecular weight of 4800 is added to said polyether polyol, polyol chain extender is added to said additives; in the above-mentioned composition, the total mass portions of polyether polyol and polymer polyol are 100 parts, the foaming agent is 1,5-3 mass parts, the mass portions of isocyanate are determined by the following way: above-mentioned all components containing hydroxyl value multiplied by the hydroxyl value corresponding to each component and then multiplied by the constant 0.155, plus the value of the foaming agent multiplied by a constant 9.665; at last the above-mentioned total number is multiplied by hardness index and then finally obtained the mass portions of isocyanate. The addition amount of said polyoxypropylene trihydroxy ether with molecular weight of 4800 is 60-80% of the weight portions of main material polyol; the weight portions of the polyol chain extender are 2-5 parts of the weight portions of main material polyol.
 2. A MDI system non-temperature sensitive memory sponge suitable for flat foam foaming process according to claim 1, wherein said polyol chain extender is polyether polyol with molecular weight of
 100. 